docs: def add(self, text="", default_continuousAdd=True):
  		"""add some turtle text"""
  		if not text and default_continuousAdd:
  			self.continuousAdd()
  		else:
  			pprefix = ""
  			for x,y in self.rdflib_graph.namespaces():
  				pprefix += "@prefix %s: <%s> . \n" % (x, y)
  			# add final . if missing
  			if text and (not text.strip().endswith(".")):
  				text += " ."
  			# smart replacements
  			text = text.replace(" sub ", " rdfs:subClassOf ")
  			text = text.replace(" class ", " owl:Class ")
  			# finally
  			self.rdflib_graph.parse(data=pprefix+text, format="turtle")